You have a secret that can ruin your life. It’s not a well-kept secret, either. Just a simple string of characters that can reveal everything about you.
The most secure system isn’t any good if it’s a total pain to access. Requiring you to remember a 256-character hexadecimal password might keep your data safe, but you’re no more likely to get into your account than anyone else.
When security by plebeian obscurity is insufficient, what do you do?